Subjects will enter the 2-week run-in period after meeting eligibility criteria at the screening visit (visit 1). During run-in subjects will have all usual asthma medications discontinued and will be placed on inhaled corticosteroids at moderate doses and leukotriene receptor antagonists will be withdrawn (LTRA wash-out). Subjects will be monitored to rule out any acute infection or symptoms consistent with an exacerbation. The run-in period will be used to assess subject compliance and understanding of study related procedures. Following the run-in, to be eligible for the randomization subjects must have an ACQ score >1.25 on the Juniper Asthma Control Questionnaire.